a romantic is a person who believes in romanticism, which is like a philosophy on life. Romantics love nature, old things like castles and churches, love poetry and beauty, and have a tendency to get carried away by ideas. This can be both bad and good, as most of the original romantics stood up for their beliefs and greatly helped England, but also went to help people in revolutions and got killed. They also tend to get randomly depressed, but this is because the weather and colors and beatiful things make them act differently than others.

Adjective: Used to describe a thing, act or object that expresses and requires intimacy beyond what usually occurs in a relationship, highly subjective and eluding understanding outside of said relationship.

Noun: Used to refer to people that either are perceived to be able to be romantic more often than others or people that believe in some kind of scheme of live where idealized love has any meaning. Often used derogatory.

Alice: It was so romantic when Ted and I went catching psychotropic toads and smoked them in abandoned factories.
Bob: WTF?

Alice: I think Bob is a romantic.
Carol: You'll never know until you try.